Lame cache can be abused to severely degrade resolver performance
In BIND 9.3.0 -> 9.11.35, 9.12.0 -> 9.16.21, and versions 9.9.3-S1 -> 9.11.35-S1 and 9.16.8-S1 -> 9.16.21-S1 of BIND Supported Preview Edition, as well as release versions 9.17.0 -> 9.17.18 of the BIND 9.17 development branch, exploitation of broken authoritative servers using a flaw in response processing can cause degradation in BIND resolver performance. The way the lame cache is currently designed makes it possible for its internal data structures to grow almost infinitely, which may cause significant delays in client query processing.
- Published
- Oct 27, 2021
- Updated
- Jun 16, 2026
- EPSS
- 10.6% · 96th percentile
- CWE
- —
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Report tools
Action score
24
Monitor
Low priority for now.
- CVSS
- 21 / 40 · 5.3 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 3 / 30 · 10.6%
CNA vs NVD score
- NVD
- 5.3
- CNA · isc
- 5.3
- agree
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| isc | bind | cpe:2.3:a:isc:bind |
| fedoraproject | fedora | cpe:2.3:o:fedoraproject:fedora |
| debian | debian linux | cpe:2.3:o:debian:debian_linux |
| netapp | h300s firmware | cpe:2.3:o:netapp:h300s_firmware |
| netapp | h300s | cpe:2.3:h:netapp:h300s |
| netapp | h500s firmware | cpe:2.3:o:netapp:h500s_firmware |
| netapp | h500s | cpe:2.3:h:netapp:h500s |
| netapp | h700s firmware | cpe:2.3:o:netapp:h700s_firmware |
| netapp | h700s | cpe:2.3:h:netapp:h700s |
| netapp | h300e firmware | cpe:2.3:o:netapp:h300e_firmware |
| netapp | h300e | cpe:2.3:h:netapp:h300e |
| netapp | h500e firmware | cpe:2.3:o:netapp:h500e_firmware |
and 11 more
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- debian debian linux10.0
- debian debian linux11.0
- debian debian linux9.0
- fedoraproject fedora33
- fedoraproject fedora34
- fedoraproject fedora35
- isc bind9.3.0 and later · before 9.11.36
- isc bind9.17.0 and later · before 9.17.19
- isc bind9.12.0 and later · before 9.16.22
- isc bind9.10.5
- isc bind9.10.7
- isc bind9.11.12
- isc bind9.11.21
- isc bind9.11.27
- isc bind9.11.29
- isc bind9.11.3
- isc bind9.11.35
- isc bind9.11.5
- isc bind9.11.6
- isc bind9.11.7
Versions reported by the vendor
Affected version ranges reported by the assigning authority (isc). Independent of NVD's CPE analysis and usually ahead of it.
ISC BIND9
- Open Source Branches 9.3 through 9.11 9.3.0 through versions before 9.11.36, Open Source Branches 9.12 through 9.16 9.12.0 through versions before 9.16.22, Supported Preview Branches 9.9-S through 9.11-S 9.9.3-S1 through versions before 9.11.36-S1, Supported Preview Branch 9.16-S 9.16.8-S1 through versions before 9.16.22-S1, Development Branch 9.17 9.17.0 through versions before 9.17.19affected
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| AlmaLinux:8 | bind | before 32:9.11.36-3.el8 | 32:9.11.36-3.el8 |
| AlmaLinux:8 | bind-chroot | before 32:9.11.36-3.el8 | 32:9.11.36-3.el8 |
| AlmaLinux:8 | bind-devel | before 32:9.11.36-3.el8 | 32:9.11.36-3.el8 |
| AlmaLinux:8 | bind-export-devel | before 32:9.11.36-3.el8 | 32:9.11.36-3.el8 |
| AlmaLinux:8 | bind-export-libs | before 32:9.11.36-3.el8 | 32:9.11.36-3.el8 |
| AlmaLinux:8 | bind-libs | before 32:9.11.36-3.el8 | 32:9.11.36-3.el8 |
| AlmaLinux:8 | bind-libs-lite | before 32:9.11.36-3.el8 | 32:9.11.36-3.el8 |
| AlmaLinux:8 | bind-license | before 32:9.11.36-3.el8 | 32:9.11.36-3.el8 |
| AlmaLinux:8 | bind-lite-devel | before 32:9.11.36-3.el8 | 32:9.11.36-3.el8 |
| AlmaLinux:8 | bind-pkcs11 | before 32:9.11.36-3.el8 | 32:9.11.36-3.el8 |
| AlmaLinux:8 | bind-pkcs11-devel | before 32:9.11.36-3.el8 | 32:9.11.36-3.el8 |
| AlmaLinux:8 | bind-pkcs11-libs | before 32:9.11.36-3.el8 | 32:9.11.36-3.el8 |
| AlmaLinux:8 | bind-pkcs11-utils | before 32:9.11.36-3.el8 | 32:9.11.36-3.el8 |
| AlmaLinux:8 | bind-sdb | before 32:9.11.36-3.el8 | 32:9.11.36-3.el8 |
| AlmaLinux:8 | bind-sdb-chroot | before 32:9.11.36-3.el8 | 32:9.11.36-3.el8 |
| AlmaLinux:8 | bind-utils | before 32:9.11.36-3.el8 | 32:9.11.36-3.el8 |
| AlmaLinux:8 | python3-bind | before 32:9.11.36-3.el8 | 32:9.11.36-3.el8 |
| Alpine:v3.12 | bind | from 9.3.0 · before 9.16.27-r0 | 9.16.27-r0 |
| Alpine:v3.13 | bind | from 9.3.0 · before 9.16.25-r0 | 9.16.25-r0 |
| Alpine:v3.15 | bind | from 9.3.0 · before 9.16.22-r0 | 9.16.22-r0 |
| Debian:10 | bind9 | before 1:9.11.5.P4+dfsg-5.1+deb10u6 | 1:9.11.5.P4+dfsg-5.1+deb10u6 |
| Debian:11 | bind9 | before 1:9.16.22-1~deb11u1 | 1:9.16.22-1~deb11u1 |
| Debian:12 | bind9 | before 1:9.17.19-1 | 1:9.17.19-1 |
| Debian:9 | bind9 | before 1:9.10.3.dfsg.P4-12.3+deb9u10 | 1:9.10.3.dfsg.P4-12.3+deb9u10 |
+39
Same product
isc: all recordsOther highest-scoring records for the same primary product.
- CVE-2015-5477named in ISC BIND 9.x before 9.9.7-P2 and 9.10.x before 9.10.2-P3 allows remote attackers to cause a denial of service (REQUIRE assertion fa58Plan
- CVE-2016-2776buffer.c in named in ISC BIND 9 before 9.9.9-P3, 9.10.x before 9.10.4-P3, and 9.11.x before 9.11.0rc3 does not properly construct responses,57Plan
- CVE-2016-1286named in ISC BIND 9.x before 9.9.8-P4 and 9.10.x before 9.10.3-P4 allows remote attackers to cause a denial of service (assertion failure an53Plan
- CVE-2020-8625A vulnerability in BIND's GSSAPI security policy negotiation can be targeted by a buffer overflow attack51Plan
- CVE-2020-8617A logic error in code which checks TSIG validity can be used to trigger an assertion failure in tsig.c51Plan
- CVE-2001-0010Buffer overflow in transaction signature (TSIG) handling code in BIND 8 allows remote attackers to gain root privileges.49Plan
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| almalinux:bind | 32:9.11.36-3.el8 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:bind-chroot | 32:9.11.36-3.el8 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:bind-devel | 32:9.11.36-3.el8 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:bind-export-devel | 32:9.11.36-3.el8 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:bind-export-libs | 32:9.11.36-3.el8 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:bind-libs | 32:9.11.36-3.el8 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:bind-libs-lite | 32:9.11.36-3.el8 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:bind-license | 32:9.11.36-3.el8 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:bind-lite-devel | 32:9.11.36-3.el8 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:bind-pkcs11 | 32:9.11.36-3.el8 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:bind-pkcs11-devel | 32:9.11.36-3.el8 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:bind-pkcs11-libs | 32:9.11.36-3.el8 · AlmaLinux:8 | Package registry (OSV) |
| alpine:bind | 9.16.27-r0 · Alpine:v3.12 | Package registry (OSV) |
| debian:bind9 | 1:9.17.19-1 · Debian:12 | Package registry (OSV) |
| opensuse:bind | 9.16.31-150400.5.6.1 · openSUSE:Leap 15.4 | Package registry (OSV) |
| opensuse:htmldoc | 1.9.12-bp153.2.15.1 · openSUSE:Leap 15.3 | Package registry (OSV) |
| red hat:bind | 32:9.11.36-3.el8 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:bind-chroot | 32:9.11.36-3.el8 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:bind-debuginfo | 32:9.11.36-3.el8 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:bind-debugsource | 32:9.11.36-3.el8 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:bind-devel | 32:9.11.36-3.el8 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:bind-export-libs-debuginfo | 32:9.11.36-3.el8 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:bind-libs | 32:9.11.36-3.el8 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:bind-libs-debuginfo | 32:9.11.36-3.el8 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:bind-libs-lite | 32:9.11.36-3.el8 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:bind-libs-lite-debuginfo | 32:9.11.36-3.el8 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:bind-license | 32:9.11.36-3.el8 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:bind-lite-devel | 32:9.11.36-3.el8 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| rocky linux:bind | 2:9.11.36-3.el8 · Rocky Linux:8 | Package registry (OSV) |
| suse:bind | 9.11.22-3.37.1 · SUSE:Linux Enterprise Software Development Kit 12 SP5 | Package registry (OSV) |
+2
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
- Kishore Kumar KothapalliInfoblox for bringing this vulnerability to our attention.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- low · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- Low
Weakness class (CWE)
—
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpChange log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
- kb.isc.org/v1/docs/cve-2021-25219
- lists.debian.org/debian-lts-announce/2021/11/msg00001.html
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EF4NAVRV4H3W4GA3LGGZYUKD3HSJBAVW/
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YGV7SA27CTYLGFJSPUM3V36ZWK7WWDI4/
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YTKC4E3HUOLYN5IA4EBL4VAQSWG2ZVTX/
- security.gentoo.org/glsa/202210-25
- security.netapp.com/advisory/ntap-20211118-0002/
- www.debian.org/security/2021/dsa-4994
- www.oracle.com/security-alerts/cpuapr2022.html
Vendor advisories and official records. Exploit/PoC links are deliberately left out.